ABSTRACT

This study explored a unique digital image analysis technique to quantify the adhesive failure (AF) in asphalt mixtures subjected to indirect tensile testing and different levels of aging and moisture conditions. Using the tensile strength ratio (TSR) in conjunction with AF, this study grouped asphalt mixture’s moisture resistance into three zones as high (TSR > 80%), moderate (70% < TSR < 80%), and low (TSR < 70%). Asphalt mixtures with AF less than 10% were grouped as highly resistant to moisture damage. Likewise, the asphalt mixtures with AF between 10%–15% were grouped as moderate and AF more than 15% was classified as asphalt mixtures with a low resistance to moisture intrusion. The association of fracture energy (FE) with proposed zones of moisture susceptibility was evaluated. The asphalt mixtures with FE higher than 5200 J/m² was found to be highly resistant to moisture damage (AF<10%). Whereas asphalt mixtures with FE lower than 3300 J/m² were less resistant (AF>15%) to moisture damage. Further, the percent loss in the coating on loose asphalt mixtures subjected to boiling water test agreed with the proposed AF limits. The findings showed that AF would help screen the moisture damage susceptible asphalt mixture stringently when used in conjunction with TSR and FE.

摘要

这项研究探索了一种独特的数字图像分析技术，可以对经过间接拉伸测试以及不同程度的老化和湿度条件的沥青混合料的粘合破坏（AF）进行量化。结合抗张强度比（TSR）和AF，本研究将沥青混合料的耐湿性分为高（TSR> 80％），中（70％<TSR <80％）和低（TSR <70％）三个区域。 ）。AF含量低于10％的沥青混合料被归类为高度耐湿气损害。同样，AF介于10％至15％之间的沥青混合物被分类为中度，AF大于15％被归类为对湿气侵入具有较低抵抗力的沥青混合物。评估了断裂能（FE）与拟议的湿气敏感性区域之间的关系。FE大于5200 J / m的沥青混合料发现²具有高度的防潮能力（AF <10％）。FE低于3300 J / m ^2的沥青混合料对湿气的抵抗力较弱（AF> 15％）。此外，经过沸水测试的松散沥青混合料的涂层损失百分比与建议的AF限值一致。研究结果表明，当与TSR和FE结合使用时，AF有助于严格筛选易受湿气损害的沥青混合料。